Changes imported from Abseil "staging" branch:

- db6fa2aed56380c6708670659c6f8603284fcc4a Rework Abseil cmake/README.md by Abseil Team <absl-team@google.com>
  - 192c7d3553bc0fe98f6935ccecff48ed785d89f0 Add function attribute ABSL_ATTRIBUTE_FUNC_ALIGN(bytes) t... by Abseil Team <absl-team@google.com>
  - 1a93e95c71c656add346a0c1771bec26417347ad Internal change by Abseil Team <absl-team@google.com>
  - 5c6d3e023a8749a5cc89f4cc6b57b6684a28b1c1 Internal change by Shaindel Schwartz <shaindel@google.com>
  - e415990ea54cf882646b0bc0a75a6e3c6741ce5f Fix testing of UTF8 characters on Windows (https://github... by Abseil Team <absl-team@google.com>

GitOrigin-RevId: db6fa2aed56380c6708670659c6f8603284fcc4a
Change-Id: I128a7ca751fa207ef272809c1b908568d187c87e

CMake/README.md

@@ -1,51 +1,51 @@
-## Abseil CMake build instructions
+# Abseil CMake Build Instructions
 
+Abseil comes with a CMake build script ([CMakeLists.txt](../CMakeLists.txt))
+that can be used on a wide range of platforms ("C" stands for cross-platform.).
+If you don't have CMake installed already, you can download it for free from
+<http://www.cmake.org/>.
 
-### Recommended usage : incorporate Abseil into an  CMake project
+CMake works by generating native makefiles or build projects that can
+be used in the compiler environment of your choice.
 
-  For API / ABI compatibility reasons, it is recommended to build
-  and use abseil in a subdirectory of your project or as an embedded
-  dependency
+For API/ABI compatibility reasons, we strongly recommend building Abseil in a
+subdirectory of your project or as an embedded dependency.
 
-  This is similar to the recommended usage of the googletest framework
-  ( https://github.com/google/googletest/blob/master/googletest/README.md )
+## Incorporating Abseil Into a CMake Project
 
-  Build and use step-by-step
+The recommendations below are similar to those for using CMake within the
+googletest framework
+(<https://github.com/google/googletest/blob/master/googletest/README.md#incorporating-into-an-existing-cmake-project>)
 
+### Step-by-Step Instructions
 
-  1- Download abseil and copy it in a sub-directory in your project.
-      or add abseil as a git-submodule in your project
+1. If you haven't done so already, integrate the Abseil dependency
+[CCTZ](https://github.com/google/cctz) into your CMake project. Consequently, the
+target 'cctz' needs to be declared in your CMake project **before** including Abseil.<br>
+Note: If you want to build the Abseil tests, you'll also need [Google Test](https://github.com/google/googletest). To disable Abseil tests, you have to pass
+`-DBUILD_TESTING=OFF` when configuring your project with CMake.
 
-  2- If not done yet, download and copy in your project the two dependencies of
-      abseil `cctz` and `googletest`
+2. Download Abseil and copy it into a subdirectory in your CMake project or add
+Abseil as a [git submodule](https://git-scm.com/docs/git-submodule) in your
+CMake project.
 
-    * cctz  https://github.com/google/cctz
-    * googletest https://github.com/google/googletest
+3. You can then use the CMake command
+[`add_subdirectory()`](https://cmake.org/cmake/help/latest/command/add_subdirectory.html)
+to include Abseil directly in your CMake project. In addition, it's possible to
+customize the name of the `cctz` target with the `-DABSL_CCTZ_TARGET=*my_cctz*` option.
 
-  3- You can then use the cmake command `add_subdirectory()` to include
-  abseil directly and use the abseil targets in your project.
+4. Add the **absl::** target you wish to use to the
+[`target_link_libraries()`](https://cmake.org/cmake/help/latest/command/target_link_libraries.html)
+section of your executable or of your library.<br>
+Here is a short CMakeLists.txt example of a project file using Abseil.
 
-    Note: Abseil requires CCTZ and the googletest framework. Consequently,
-    the targets  `gtest`, `gtest_main`, `gmock` and `cctz` need
-    to be declared in your project before including abseil with
-    `add_subdirectory`. However, if abseil is compiled with
-    `-DBUILD_TESTING=OFF`, then `gtest`, `gmock` and `gtest_main` are not
-    required. In addition, it's possible to override the name of the `cctz`
-    target to a custom one with option `-DABSL_CCTZ_TARGET=*my_cctz*`.
+```cmake
+cmake_minimum_required(VERSION 2.8.12)
+project(my_project)
 
-  4- Add the absl:: target you wish to use to the `target_link_libraries()`
-    section of your executable or of your library
+set(CMAKE_CXX_FLAGS "-std=c++11 -stdlib=libc++ ${CMAKE_CXX_FLAGS}")
 
-
-      Here is a short CMakeLists.txt example of a possible project file
-      using abseil
-
-      cmake_minimum_required(VERSION 2.8.12)
-      project(my_project)
-
-      set(CMAKE_CXX_FLAGS "-std=c++11 -stdlib=libc++ ${CMAKE_CXX_FLAGS}")
-
-      if (MSVC)
+if(MSVC)
   # /wd4005  macro-redefinition
   # /wd4068  unknown pragma
   # /wd4244  conversion from 'type1' to 'type2'
@@ -53,28 +53,30 @@
   # /wd4800  force value to bool 'true' or 'false' (performance warning)
   add_compile_options(/wd4005 /wd4068 /wd4244 /wd4267 /wd4800)
   add_definitions(/DNOMINMAX /DWIN32_LEAN_AND_MEAN=1 /D_CRT_SECURE_NO_WARNINGS)
-      endif()
-
-      add_subdirectory(googletest)
-      add_subdirectory(cctz)
-      add_subdirectory(abseil-cpp)
-
-      add_executable(my_exe source.cpp)
-      target_link_libraries(my_exe absl::base absl::synchronization absl::strings)
-
-
-As of this writing, that pull request requires -DBUILD_TESTING=OFF as it doesn't correctly export cctz's dependency on Google Benchmark.
-
-    You will find here a non exhaustive list of absl public targets
-
-      absl::base
-      absl::algorithm
-      absl::container
-      absl::debugging
-      absl::memory
-      absl::meta
-      absl::numeric
-      absl::strings
-      absl::synchronization
-      absl::time
-      absl::utility
+endif()
+
+add_subdirectory(googletest)
+add_subdirectory(cctz)
+add_subdirectory(abseil-cpp)
+
+add_executable(my_exe source.cpp)
+target_link_libraries(my_exe absl::base absl::synchronization absl::strings)
+```
+
+### Available Abseil CMake Public Targets
+
+Here's a non-exhaustive list of Abseil CMake public targets:
+
+```cmake
+absl::base
+absl::algorithm
+absl::container
+absl::debugging
+absl::memory
+absl::meta
+absl::numeric
+absl::strings
+absl::synchronization
+absl::time
+absl::utility
+```

absl/base/attributes.h

@@ -527,6 +527,16 @@
 #define ABSL_ATTRIBUTE_PACKED
 #endif
 
+// ABSL_ATTRIBUTE_FUNC_ALIGN
+//
+// Tells the compiler to align the function start at least to certain
+// alignment boundary
+#if ABSL_HAVE_ATTRIBUTE(aligned) || (defined(__GNUC__) && !defined(__clang__))
+#define ABSL_ATTRIBUTE_FUNC_ALIGN(bytes) __attribute__((aligned(bytes)))
+#else
+#define ABSL_ATTRIBUTE_FUNC_ALIGN(bytes)
+#endif
+
 // ABSL_CONST_INIT
 //
 // A variable declaration annotated with the `ABSL_CONST_INIT` attribute will

absl/base/internal/malloc_hook.cc

@@ -437,6 +437,7 @@ static inline bool InHookCaller(const void* caller) {
   return ADDR_IN_ATTRIBUTE_SECTION(caller, google_malloc) ||
          ADDR_IN_ATTRIBUTE_SECTION(caller, malloc_hook) ||
          ADDR_IN_ATTRIBUTE_SECTION(caller, blink_malloc);
+
   // We can use one section for everything except tcmalloc_or_debug
   // due to its special linkage mode, which prevents merging of the sections.
 }

absl/strings/str_split_test.cc

@@ -621,7 +621,7 @@ TEST(Split, StringDelimiter) {
 
 TEST(Split, UTF8) {
   // Tests splitting utf8 strings and utf8 delimiters.
-  std::string utf8_string = "\u03BA\u1F79\u03C3\u03BC\u03B5";
+  std::string utf8_string = u8"\u03BA\u1F79\u03C3\u03BC\u03B5";
   {
     // A utf8 input std::string with an ascii delimiter.
     std::string to_split = "a," + utf8_string;
@@ -641,8 +641,8 @@ TEST(Split, UTF8) {
   {
     // A utf8 input std::string and ByAnyChar with ascii chars.
     std::vector<absl::string_view> v =
-        absl::StrSplit("Foo h\u00E4llo th\u4E1Ere", absl::ByAnyChar(" \t"));
-    EXPECT_THAT(v, ElementsAre("Foo", "h\u00E4llo", "th\u4E1Ere"));
+        absl::StrSplit(u8"Foo h\u00E4llo th\u4E1Ere", absl::ByAnyChar(" \t"));
+    EXPECT_THAT(v, ElementsAre("Foo", u8"h\u00E4llo", u8"th\u4E1Ere"));
   }
 }
 

absl/synchronization/blocking_counter.h

@@ -93,4 +93,5 @@ class BlockingCounter {
 };
 
 }  // namespace absl
+
 #endif  // ABSL_SYNCHRONIZATION_BLOCKING_COUNTER_H_